The invention provides a torch for welding the inside of bores in a tungsten inert gas welding process and particularly adapted for welding in relatively small bores which are not readily accessible by electrodes. A typical application is for welding the laminations of a stator. In bore welding, copper rings are typically positioned at opposite ends of the bore and held in place by the mounting or clamping assembly for the workpiece. Desirably, the electrode can be moved axially through the bore to provide in one stroke a welded band or seam. It is also desirable that the electrode can be rotated or the workpiece indexed to provide one or more seam welds. The conductor, which must extend from the torch mounting head to the electrode, must be insulated from the bore. In addition, the high temperatures at the welding zone also require heat shielding and insulation of the electrode and conductor to minimize destruction caused by the heat.